Reproduction steps:
1. Open the attached “UndoSerializedFields” project
2. Open the “Assets/BugReport/New Scene” Scene
3. In the Hierarchy window, select “ReferencingComponent” GO
4. In the Inspector window, observe “My Reference Type” variable
5. In the Hierarchy window, delete “GameObjectToReference” GO
6. Repeat steps 3 and 4
7. Toggle the “Some Useless Toggle” property and repeat step 4
8. Undo actions (cmd + z) until “GameObjectToReference” GO is restored
9. In the Hierarchy window, select “ReferencingComponent” GO and repeat step 4 and 7
Expected result: The reference type is updated instantly to “Object” type after deleting and to “GameObject” type after restoring the “GameObjectToReference”
Actual result: The reference type is only updated when a forced deserialization occurs (e.g., toggling an Inspector property)
Reproducible with: 2022.3.58f1, 6000.0.39f1, 6000.1.0b7, 6000.2.0a4
Reproducible on: macOS Sequoia 15.3.1 (M1 Max), Windows 11
Not reproducible on: No other environments tested